Vegetable Compound Shields Rodents From Deadly Radiation

WASHINGTON, DC, October 16, 2013 (ENS) – A compound derived from cruciferous vegetables such as broccoli, cauliflower, cabbage and kale can protect rats and mice from lethal doses of radiation, Georgetown University Medical Center researchers have discovered.

Their study, published Tuesday in the journal “Proceedings of the National Academy of Sciences” suggests the substance, already shown to be safe for humans, may protect normal tissues during radiation therapy for cancer treatment.

The scientists say the compound also may prevent or mitigate sickness from radiation exposure during a nuclear disaster.

The compound 3,3′-diindolylmethane, known as DIM, has previously been found to have cancer preventive properties and multiple anticancer effects in experimental models.

“DIM has been studied as a cancer prevention agent for years, but this is the first indication that DIM can also act as a radiation protector,” says the study’s corresponding author, Eliot Rosen, MD, PhD, of Georgetown Lombardi Comprehensive Cancer Center.

For the study, the researchers irradiated rats with lethal doses of gamma ray radiation. The animals were then treated with a daily injection of DIM for two weeks, starting 10 minutes after the radiation exposure.

The result was stunning, said Rosen, a professor of oncology, biochemistry and cell and molecular biology, and radiation medicine.

“All of the untreated rats died, but well over half of the DIM-treated animals remained alive 30 days after the radiation exposure,” he said.

Rosen said that DIM also provided protection whether the first injection was administered 24 hours before or up to 24 hours after the radiation exposure.

Irradiated mice treated with DIM had less reduction in red blood cells, white blood cells and platelets. These side effects are often seen in patients undergoing radiation treatment for cancer.

Rosen says this study points to two potential uses of the compound.

“DIM could protect normal tissues in patients receiving radiation therapy for cancer, but could also protect individuals from the lethal consequences of a nuclear disaster,” he said.

Rosen and study co-authors Saijun Fan, PhD, and Milton Brown, MD, PhD, are co-inventors on a patent application filed by Georgetown University related to the use of DIM and DIM-related compounds as radioprotectors.

This research was supported by U.S. Public Health Service Grants, a grant from the Center for Drug Discovery at Georgetown University, and other Georgetown funding.